1. Field of the Invention
The present invention relates generally to an apparatus for collecting, processing and analyzing a liquid specimen in a fully integrated system. This invention also relates to a method for collecting, processing, and analyzing a liquid specimen.
2. Description of the Related Art
Diagnostic testing throughout the world is currently carried out using a variety of different specimen types. Many of the samples tested, such as whole blood, serum, oral fluid, plasma, cerebrospinal fluid and others, are liquid.
Testing for infectious diseases under laboratory conditions typically involves use of a blood serum specimen obtained by removing the blood cells from an intravenous blood sample by centrifugation. The sample is first drawn from the patient by a trained phlebotomist. The serum sample so obtained is then tested under laboratory conditions using one of a number of methodologies, such as Enzyme Linked Immuno Sorbent Assay (ELISA), Immunofluorescence (IFA), Latex Agglutination (LA), or any of a number of automated instrument platforms employing chemiluminescence, fluorescence or other sensitive technologies. As there are other known diagnostic technologies in place, this is by no mean an exhaustive list.
Although serum testing under laboratory conditions has traditionally constituted the technique of choice, there is now a growing trend to move testing closer to the patient and use alternative specimen matrices such as whole blood and others. In other words, the sample is drawn from the patient, processed and analyzed more rapidly, often while the patient is still in attendance. The recent advance known as xe2x80x9cnear-patientxe2x80x9d or xe2x80x9cpoint-of-carexe2x80x9d testing has caused a major shift in the way testing is done. Statistics show growth of over 20% per annum in this mode of testing for each of the last four years.
Such growth in this mode of testing has resulted in the increased use of alternate specimen types (e.g. whole-blood or oral fluid) not requiring the use of trained phlebotomists or additional steps to separate red blood cells from the required specimen. Rather, the sample can be drawn from the patient and processed directly. As a consequence, results can now be obtained, analyzed and conveyed to the patient while the patient or subject is still in the presence of the healthcare provider. This avoids the need for repeat patients or the need for the patient to contact the healthcare provider at a future time to obtain their test results.
Point-of-care (POC) testing therefore offers the advantage of giving the physician (and, if the physician chooses, the patient) immediate results, in contrast to conventional testing, where there is a waiting period, that could be anywhere from several hours to weeks, during which the specimens are transported to a laboratory testing facility, processed, and results sent to the physician.
It is standard in the industry to confirm infectious disease test results by repeat testing, often by a more sensitive methodology, especially when the testing is for potentially life-threatening diseases such as HIV, Hepatitis C, Hepatitis B, and so on. This applies regardless of whether the testing is performed in a laboratory or at the point-of-care. The second test used to confirm the result of the primary test is known as a xe2x80x9cconfirmatoryxe2x80x9d or xe2x80x9cconfirmationxe2x80x9d test and typically uses a different methodology to confirm a diagnosis or otherwise. For instance in HIV diagnostics, Western Blot or ELISA methods may be used. In all instances a second specimen will be required. Owing to the serious nature of such testing, anything that can expedite sample processing is of tremendous importance.
In the case of laboratory testing, there may be sufficient specimen material remaining from the initial blood draw to carry out confirmation testing.
However, no rapid (in-office) tests are known which include a mechanism to collect a specimen for confirmatory testing at the time of the first patient visit to the healthcare facility.
The present invention is directed to a sample testing device having a buffer container that can contain buffer fluid therein, a filter having a securement for holding a test strip, the test strip, an end of which is held by the securement, a test strip container having a receptacle dimensioned and disposed to accommodate the filter, so that when the filter is held therein the test strip is disposed in the receptacle, and a sample collector for holding a sample.
In an embodiment, the sample collector is shaped to receive the buffer container, and the sample collector has a channeling member and a piercing member which, when the buffer container is placed in the sample collector, pierces the buffer container so that the buffer fluid in the buffer chamber contacts the sample and passes through the lumen to the filter. As buffer fluid flows through the lumen of the sample collector the buffer fluid that has contacted the sample passes through the filter to the test strip.
In a further embodiment, the sample collector has both a top and a bottom opening, wherein said top opening is shaped to receive said buffer container and said bottom opening is shaped to receive the filter. The sample collector also houses a piercing member which pierces the buffer container when the buffer container is placed in the top opening of the sample collector, thereby releasing the buffer fluid so that the buffer fluid contacts the sample. In yet another embodiment of the present invention, the sample collector has a pump which draws the sample into the sample collector.
This invention also relates to a sample testing device that includes a buffer container which can contain buffer fluid, the buffer container having a weakened portion, a filter having a securement for holding a test strip, the test strip, an end of which is held by the securement, and a test strip container having a receptacle dimensioned and disposed to accommodate the filter, so that when the filter is accommodated by the test strip container, the test strip is disposed in the receptacle. The invention also includes a sample collector for holding a sample therein and which is shaped to receive the buffer container, the sample collector having a channeling member. When the buffer container is squeezed, the weakened portion fails and the buffer fluid in the buffer chamber contacts the sample and passes through the lumen of the channeling member to the filter. As the buffer fluid flows through the lumen of the sample collector the buffer fluid that has contacted the sample passes through the filter to the test strip.
This invention also provides a sample testing device that includes a buffer container which can contain buffer fluid therein, a filter having a securement for holding a test strip, the test strip, an end of which is held by the securement, a test strip container having a receptacle dimensioned and disposed to accommodate the filter, so that when the filter is held therein the test strip is disposed in the receptacle, and a sample collector including a pump for holding the sample.
Another aspect of this invention is a method for testing a sample. This is done by obtaining the sample, placing the sample in a sample collector, positioning a buffer container having buffer fluid therein above the sample collector, positioning the sample container above a filter, the filter having a test strip in contact therewith, and causing the buffer fluid to flow downward from the buffer container over the sample and through the filter to the test strip.